Improvement in dooes poe fuenaces



W. W. CRANE.

DOOR 'FOR FURNAGBS.

No. 82,294. Patented Sept.. 22,1868.

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WILLIAM W. CRANE,- OF PHILADELPHIA, PENNSYLVANIA.

Letters Patent No. 82,294, dated September 22, 18.68. g

IMPROVEMENT IN DOORS FOR FURNACES.

TO ALL WHOM IT MAY'GONGERN:

Be it known that I, WILLIAM W. CRANE, of the city of Philadelphia, andState of'Pennsylvania, have invented-a new and useful Ash-Pit Door forFurnaces, Heaters, &c.; and I do hereby declare that the following isafizll, clear, and; exact description of the same, reference being hadto the accompanying sheet oi: drawings, and to the letters-of referencemarked thereon, making part of this specification, in whinh Figural is aplan view, and Figure 2 is a sectioned elevation. Similar letters referto similar parts'in the tyroviws. My invention consists of anair-tight'ash pit door; 'which is so constructed, with reference to theflange or rib on the ash-door plate, as to have't ne means of regulating'the'qufintity of air admitted to the fueLthe-doo'r, having a valve oropening; and to this end I form a rim'or elevation, A, on the door-plateB, which conforms completely with the. inner" surface of the rima of thedoor C; the'upb'er xdge or-top of the elevation A,

'takin'g against the under surface of the top'oi the door, and the.bottom or edge'oflthe rim a restingagainst the door-plate, thusaccurately fitting on all three surfaces, thereby making'a practicallyair-tight door. The door has a hole or opening, 6,-h'hi0h is regulatedby a slider, c, at which the necessary ouantity of air is admitted topreserve comhustion. I v

The door isoperated like all furnace-doors; it turns on the'pin D, whichtakes through its-lugs, E, and

the jaws G G, of'the door-plate B; When closed, the wei ht of it is inpart taken from the jaws by the projection H, in the front of the door,taking on to the projection I, of the door-plate.

The door 0 and the flange A should be accurately cast, so as not torequire fitting; the vitreous surface of the metal is thereby retained,and it is, of consequence, prevented from rusting, and the door keptair-tight What I'claim as my invention, and desire to secure by LettersPatent, is-

Ihe door-plate B, rimor elevation A, and the 'door C,.when constructed'and arranged suhstant ially'as and for the purpose shown and described.

In testimony whereof, I hereunto sign my name to this specification inpresence oftwo subscribing witnesses.

WILLIAM CRANE.

Witnesses:

Fnsncrs D. Pssronrus, C. C. Seaman.

